A. J. Cole 2026-11-05
A. J. Cole and A. J. T. Davie introduced Euclid game in a 1969 paper. They explicitly designed it to illustrate an algorithm for a winning strategy, making a familiar arithmetic procedure into a problem of combinatorial game theory.[ref]
The Euclidean algorithm repeatedly subtracts multiples of the smaller integer from the larger. Allowing a player to choose the multiple creates branching choices: termination alone is no longer the main question, because the player also cares who makes the last legal move. The terminal convention must therefore accompany any strategy statement.
A. J. T. Davie 2026-11-05
A. J. T. Davie coauthored A Game Based on the Euclidean Algorithm and a Winning Strategy for It by A. J. Cole and A. J. T. Davie with A. J. Cole. The original publisher record verifies the initials and joint authorship.[ref]
Their Euclid game turns the Euclidean algorithm into a contest: a legal subtraction is chosen by a player, so computing a greatest common divisor becomes a question about winning positions. The example connects an arithmetic algorithm with a constructive winning strategy in combinatorial game theory.